Leakiest streets in SM4

60.9%

Band D or below

13954

Certificates

62.2

Average rating

£233

Avg potential saving / yr

What this means

Across 13954 energy certificates in SM4, 8495 (60.9%) are rated band D or below. The average current rating is 62.2 out of 100, which the recommended improvements on those certificates would lift to about 80.4. The average estimated annual heating cost is £703, falling to about £470 after the recommended work – a saving of roughly £233 a year.

A B C D E F G

A 0.1% B 4.6% C 34.5% D 44.6% E 13.3% F 2.1% G 0.9%

Every figure is computed across the certificates in this area – no individual property is identified or listed.

How SM4 compares

Set against the average across the 3,339,357 energy certificates in our dataset (average current rating 67.8, with 51.7% band D or below):

Band D or below here is 60.9%, 9.2 points higher (leakier).
The average current rating here is 62.2, 5.6 points below the wider-dataset average.

Indicative comparison against the certificates we hold, not an official national statistic. Check the official source for area statistics.

What the certificates say about the fabric

The most common construction descriptions recorded across these certificates. Percentages are of certificates where the field was recorded.

Walls

Solid brick, as built, no insulation (assumed) – 37.5%
Cavity wall, as built, no insulation (assumed) – 30.0%
Cavity wall, filled cavity – 10.0%

Recorded as having no wall insulation: 67.5%.

Roofs

Pitched, no insulation (assumed) – 17.5%
Pitched, 250 mm loft insulation – 12.5%
Pitched, 200 mm loft insulation – 10.0%

Recorded as having no roof insulation: 25.0%.

Glazing

Fully double glazed – 85.2%
Partial double glazing – 7.4%
Mostly double glazing – 3.7%

Main heating

Boiler and radiators, mains gas – 92.5%
Room heaters, electric – 2.5%
Portable electric heating assumed for most rooms – 2.5%

Retrofit measures for this housing stock

Based on the construction recorded on the certificates here, these guides cover the measures that most often apply, with typical UK costs and savings cited to public sources.

All retrofit guides

What insulation adds in SM4

See the average current-to-potential uplift and the estimated heating-cost saving for this area.